Pierre-Loup Griffais, a developer from Valve, announced on Twitter today (27th) that the team is optimizing the performance of Eldon's Ring of Law on the Steam Deck platform. He said the optimization patch for severe stuttering is expected to be fixed in next week's Proton release, which players can currently test first on the Proton beta.
If you're a steam deck player, you can enter the Proton beta by first searching for Proton Experimental in the Steam Deck library and right-clicking on the Properties menu to enter Betas. Then select bleeding-edge from the drop-down box to update.
"Eldon's Ring of Law" was released on February 25, and the PC version of the game had optimization problems, resulting in bad phenomena such as frame drops. At present, FromSoftware and Bandai Namco are troubleshooting the problem, and the official will optimize and update it in the future.